A resistance paste is generally applied to film-type resistors such as, for example, fixed resistors and semi-adjustable resitors. Basically such resistors consist of a conducting film or carbon deposited on an insulating substrate. The conducting film is generally produced by applying a resistance paste to an insulating disk or square plate of alumina or resin, and then heat-treating the coating in air at a suitable temperature. Thus, the electrical properties of the resistors depend on the physical properties of the components of the resistance paste.
The resistance paste of the art generally comprises a carbon powder such as carbon black and graphite suspended in a binder of a thermosetting resin. If the occasion demands, the paste further contains organic or inorganic fillers. However, the carbon powder and binder resin used have a large negative temperature coefficient of resistance so that the resistors produced have a large negative temeprature coefficient of resistance. In particular, the temperature coefficient of resistance shifts to the negative side with an increase of resistance value, or an increase of binder resin content in the conducting film of the resistor. In addition, the resistors possess a large change rate of resistance with temperature when used under severe operating conditions such as, for example, those of 60.degree. C. and 95% humidity, or a high temperature atmosphere of 125.degree. C. Accordingly, it is impossible to use these resistors in applications in which greater stability of resistance with temperature and humidity is demanded.